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Two studies that examine whether the forgetting caused by the processing demands of working memory tasks is domain-general or domain-specific are presented. In each, separate groups of adult participants were asked to carry out either verbal or nonverbal operations on exactly the same processing materials while maintaining verbal storage items. The imposition of verbal processing tended to produce greater forgetting even though verbal processing operations took no longer to complete than did nonverbal processing operations. However, nonverbal processing did cause forgetting relative to baseline control conditions, and evidence from the timing of individuals' processing responses suggests that individuals in both processing groups slowed their responses in order to "refresh" the memoranda. Taken together the data suggest that processing has a domain-general effect on working memory performance by impeding refreshment of memoranda but can also cause effects that appear domain-specific and that result from either blocking of rehearsal or interference. (Contains 5 figures, 5 tables and 4 footnotes.)

Past research suggests that children begin to phonologically rehearse at around 7 years of age. Less is known regarding the development of refreshment, an attention-based maintenance mechanism. Therefore, the use of these two maintenance methods by 6- and 8-year-olds was assessed using memory span tasks that varied in their opportunities for maintenance activity. Experiment 1 showed that nonverbal processing impaired both groups' performance to similar extents. Experiment 2 employed phonologically similar or dissimilar memory items and compared the effects of verbal versus nonverbal processing on recall. Both groups showed evidence of phonological maintenance under nonverbal processing but not under verbal processing. Furthermore, nonverbal processing again impaired recall. Verbal processing was also more detrimental to performance in 8-year-olds than in 6-year-olds. Together, the results suggest that nonverbal processing impairs recall by obstructing refreshment and that developmental change in maintenance between 6 and 8 years of age consists primarily of an increase in phonological rehearsal. (Contains 2 figures and 3 tables.)

To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.jml.2005.01.015 Byline: Philip A. Higham, Helen Tam Keywords: Cued recall; Generate-recognize; Metacognition; Encoding specificity Abstract: Three experiments examined generation, recognition, and response bias in the original encoding-specificity paradigm using the type 2 signal-detection analysis advocated by . Experiments 1 (pure-list design) and 2 (mixed-list design) indicated that some guidance regarding the strength of the associative relationship between the test cue and target greatly improved strong-cue target production relative to no guidance, and that this effect was attributable to improved generation, as well as recognition. Problems with generating candidates for response during standard cued recall was further shown in Experiment 3, where despite having the opportunity to provide multiple responses for each cue, participants' ability to produce the targets remained poor. The results are discussed in terms of traditional and modern generate-recognize theory, metacognition, and dual-route models of recall. Author Affiliation: School of Psychology, University of Southampton, Highfield, Southampton SO17 1BJ, UK Article History: Received 9 August 2004; Revised 20 January 2005 Article Note: (footnote) [star] Philip A. Higham and Helen Tam, School of Psychology, University of Southampton. Preparation of this article was supported by a research grant from the British Academy. Portions of this research were presented at the 43rd annual meeting of the Psychonomic Society, November, 2002 in Kansas City, Missouri, USA, and at the 45th annual meeting of the Psychonomic Society, November, 2004 in Minneapolis, Minnesota, USA. We thank Nina Eskriett, Wendy Kneller and David Brook for research assistance. We thank Harry Bahrick, Chuck Brainerd, Morris Goldsmith, Asher Koriat, Steve Lindsay, Doug Nelson, and Mike Watkins for helpful comments on earlier drafts of this article.

We propose an adjoint-variable approach to design-sensitivity analysis with time-domain methods based on structured grids. Unlike conventional adjoint-based methods, it does not require analytical derivatives of the system matrices. It is simple to implement with existing computational algorithms such as the finite-difference time-domain (FDTD) technique. The resulting FDTD algorithm produces the response and its gradient in the design parameter space with two simulations regardless of the number of design parameters. The proposed method is validated by the adjoint-based FDTD analysis of waveguide structures with metallic boundaries. Index Terms--Adjoint variable methods, design-sensitivity analysis, finite-difference time-domain (FDTD) methods.

The theory of electromagnetic (EM) potentials is as old as the Maxwell equations, which treat the field vectors E and H directly. Yet the vector and scalar potentials are often regarded as nothing more than an auxiliary mathematical concept, which does not necessarily reflect a physically existing phenomenon. This widely accepted opinion does not have sound theoretical or experimental validation. The EM potentials are as 'real' as the field vectors--they describe observable phenomena and play a crucial role in the explanation of light-matter interactions, radiation, and propagation. We discuss the methodological value of the potential formalism in electromagnetism and the advantages of the potential-based computational approaches in EM analysis. The key points of the discussion are supported by examples of the analysis of classical problems such as the radiation from a small dipole and the field propagation in waveguide structures: a waveguide bend and an H-plane filter. These examples include animations of the propagation of the EM-field potentials and the respective field vectors. Index Terms--Electromagnetic (EM) potentials, EM theory, EM transient analysis.

In this paper, absorbing boundary conditions (ABCs) for adjoint problems with a backward time variable are derived from first principles. It is shown that all single-layer ABCs for the adjoint backward time problem, which are based on the one-way wave equation, have the same form as for the original forward time problem. In the case of the adjoint perfectly matched layer (PML) ABC, the signs before the spatial derivatives are opposite to those in the PML ABC of the original forward time problem. To verify the theoretical findings, the numerical reflections from the adjoint ABCs are investigated in a microstrip-line example. The reflections from the ABCs of the forward- and backward time schemes are shown to be identical for the same type of ABCs. Index Terms--Absorbing boundary conditions (ABCs), adjoint problems, design sensitivity analysis, finite-difference time-domain (FDTD) method, perfectly matched layer (PML).

Introduction and objective: Error-monitoring processes, defined as slowdown in reaction time on the first correct item following an error, are important to skill acquisition and may be impaired in children with ADHD [1, 2]. We sought to determine whether error related processes may explain poor skill acquisition in ADHD. Methods: Children with ADHD (n = 28), non-ADHD controls (n = 38), and young adults (n = 37) completed 400 trials (5 blocks) of a categorization learning paradigm [3]. Results: In the early stages of the task, children with and without ADHD exhibited less post error slowing (PES) than adults [F(2,100) = 3.53, p = 0.03, ηp2 = 0.07]. PES predicted overall accuracy for adults [F(1,35) = 10.78, p < 0.01, R2 = 0.24] but not for children [ADHD: F(1,24) = 0.00, p = 0.95, R2 = 0.00; control: F(1,36) = 0.78, p = 0.38, R2 = 0.02]. PES predicted accuracy in the final block of trials (i.e., when maximal learning was achieved) for adults [F(1,35) = 10.24, p < 0.01, R2 = 0.23] and controls [F(1,36) = 6.41, p = 0.02, R2 = 0.15], but not for children with ADHD [F(1,24) = 1.42, p = 0.25, R2 = 0.06]. Discussion/conclusion: The ability to utilize performance feedback is not fully developed in school age children. Compared to controls, children with ADHD show less behavioral responsiveness to error in a learning task. These results have implications for the development of psychoeducational programs for children with ADHD. [ABSTRACT FROM AUTHOR]

To synthesize current knowledge of the impact of pediatric neuropsychological evaluations on child functioning, we conducted a systematic review of the literature on parents' overall satisfaction with their child's evaluation and perceptions of how helpful the evaluation was for understanding their child's abilities and how useful the evaluation was for providing actionable information to elicit change. Parent satisfaction is important in this context because studies on healthcare consumption indicate a substantial relationship between patient satisfaction with services and implementation of recommendations and follow-up care. We followed PRISMA guidelines to conduct a systematic review of the literature on parent perception of pediatric neuropsychological evaluations for children aged 3-21 years. Using a set of predefined search terms, we identified 1,163 abstracts across PubMed, PsycINFO, Cochrane Library, and Web of Science electronic databases and included 12 studies in our qualitative synthesis. In general, parents reported high levels of satisfaction with their child's evaluation. Feedback from the evaluation was helpful for understanding their child's pattern of strengths and weaknesses and included useful information for obtaining support. Although parents did report improvement in their child's functional participation in home, school, and community settings, they tended to rate the usefulness of the evaluation for eliciting change lower than their overall satisfaction with the evaluation or how helpful the evaluation was for understanding their child's abilities. Additional effort appears to be needed for pediatric neuropsychological evaluations recommendations to result in durable, meaningful change in child functioning.

The renal vasopressin V(2) receptor (V(2)R) plays a critical role in physiological and pathophysiological processes associated with arginine vasopressin (AVP)-induced antidiuresis. Because clinical data suggests that females may be more prone to hyponatremia from AVP-mediated antidiuresis, we investigated whether there are sex differences in the expression and function of the renal V(2)R. In normal Sprague-Dawley rat kidneys, V(2)R mRNA and protein expression was 2.6- and 1.7-fold higher, respectively, in females compared with males. To investigate the potential physiological implications of this sex difference, we studied changes in urine osmolality induced by the AVP V(2)R agonist desmopressin. In response to different doses of desmopressin, there was a graded increase in urine osmolality and decrease in urine volume during a 24-h infusion. Females showed greater mean increases in urine osmolality and greater mean decreases in urine volume at 0.5 and 5.0 ng/h infusion rates. We also studied renal escape from antidiuresis produced by water loading in rats infused with desmopressin (5.0 ng/h). After 5 days of water loading, urine osmolality of both female and male rats escaped to the same degree physiologically, but V(2)R mRNA and protein in female kidneys was reduced to a greater degree (-63% and -73%, respectively) than in males (-32% and -48%, respectively). By the end of the 5-day escape period, renal V(2)R mRNA and protein expression were reduced to the same relative levels in males and females, thereby abolishing the sex differences in V(2)R expression seen in the basal state. Our results demonstrate that female rats express significantly more V(2)R mRNA and protein in kidneys than males, and that this results physiologically in a greater sensitivity to V(2)R agonist administration. The potential pathophysiological implications of these results are that females may be more susceptible to the development of dilutional hyponatremia because of a greater sensitivity to endogenously secreted AVP.